// The MIT License (MIT)
//
// Copyright (c) 2015 Markus Herb
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
#ifndef KALMAN_KALMANFILTERBASE_HPP_
#define KALMAN_KALMANFILTERBASE_HPP_

#include "Matrix.hpp"
#include "Types.hpp"

namespace Kalman {

/**
 * @brief Abstract base class for all Kalman Filters
 *
 * @param StateType The vector-type of the system state (usually some type
 * derived from Kalman::Vector)
 */
template <class StateType>
class KalmanFilterBase {
 public:
  static_assert(
      /*StateType::RowsAtCompileTime == Dynamic ||*/ StateType::
              RowsAtCompileTime > 0,
      "State vector must contain at least 1 element" /* or be dynamic */);
  static_assert(StateType::ColsAtCompileTime == 1,
                "State type must be a column vector");

  //! Numeric scalar type
  typedef typename StateType::Scalar T;

  //! Type of the state vector
  typedef StateType State;

 protected:
  //! Estimated state
  State x;

 public:
  /**
   * Get current state estimate
   */
  const State& getState() const { return x; }

  /**
   * @brief Initialize state
   * @param initialState The initial state of the system
   */
  void init(const State& initialState) { x = initialState; }

 protected:
  /**
   * @brief Protected constructor
   */
  KalmanFilterBase() {}
};

}  // namespace Kalman

#endif
